1. Field of the Invention
The present invention relates generally to an enclosure for interconnecting preterminated optical fibers, and more specifically, to an enclosure having at least one connector port and at least one preterminated fiber optic connector that provides access to the preterminated connectors from the exterior of the enclosure.
2. Description of the Related Art
Optical fiber cable is used for a variety of applications including voice communications, data transmission and the like. As a result of the increase in demand, fiber optic networks typically include an ever-increasing number of access points in which one or more optical fibers are branched from a distribution cable. These access points provide an increase in the number of connections in a given area and may be used to supply “fiber-to-the-premises” (FTTP). Based on the increase in the number of access points, and based on the unique physical needs of the optical fibers themselves, an enclosure is needed for protecting, handling, connecting and maintaining the optical fibers and their respective connectors. The enclosure should provide protection of the access point, the branched fibers and the connectors from environmental and mechanical factors, such as weather and stress.
Branching a distribution cable may involve branching and/or splicing one or more optical fibers that make up the cable. Distribution cables may range in length from meter to kilometer lengths, and may comprise a plurality of access points located at predetermined positions along their length. Drop cables, typically smaller than distribution cables, may be routed from the distribution cable to predetermined locations, such as a “network interface device” (NID) or a “network access point” (NAP). In various conventional drop cable designs, a technician may be responsible for accessing and splicing specific optical fibers of a distribution cable in the field. This costly and time consuming process requires sending a technician to the site, removing a portion of the cable sheath at a predetermined location, locating the appropriate optical fibers, cutting the appropriate optical fibers, branching and/or splicing the optical fibers to a drop cable optical fiber and installing an enclosure. In addition, conventional designs typically include a splice tray mounted within the enclosure for handling the splice point and storing slack cable. Using these conventional designs, if it is desired to service or alter the splice point, or to branch an additional optical fiber at the same access point, the enclosure must be opened and entered.
Optical fibers that have been accessed from a distribution cable must be protected from mechanical stresses, such as bending and tensile forces. A minimum bend radius, such as about 1.50 inches, must be maintained in order to properly transmit light through the core of the optical fiber. Too great a tensile force applied to an optical fiber, such as that applied by the weight of a drop cable or environmental factor, may damage the drop cable, splice point, distribution cable and other branched optical fibers. Conventional enclosure design does not adequately provide for bend radius control and fiber travel limitation. More importantly, conventional enclosure design does not allow access to the optical fibers from the exterior of the enclosure, while still providing for bend radius and travel control. In optical fiber enclosures, it is often necessary to clean or service the connectors. To do this, it is necessary to remove some quantity of optical fiber length from the enclosure. If two much length is pulled, two problems may occur: The first is that the optical fiber within the enclosure may be pulled around a tight corner or bend, exceeding the bend radius of the fiber and causing damage. The second is that the fiber may be damaged while pushing it back into the enclosure. Conventional enclosure design requires that special care be taken to not exceed the minimum bend radius when opening an enclosure to access the optical fibers contained therein. Thus, conventional enclosure design requires that a field technician spend extra time and effort to ensure that the optical fiber integrity is not compromised during cleaning and servicing procedures.
What is desired is an enclosure that allows for damage-free fiber slack removal and replacement during connector cleaning and servicing. Further, what is desired is a manufactured preterminated optical fiber cable comprising a plurality of factory or field-installed enclosures located at predetermined positions along the cable length, wherein the enclosure architecture allows access to preterminated connectors from the exterior of the enclosure. What is further desired is an enclosure comprising at least one connector port that provides access to preconnectorized optical fibers, which will lead to rapid and low-cost drop cable installation. The enclosure should be capable of handling and protecting the optical fibers and their respective connectors, provide for bend radius control of the optical fibers and allow access to the connectors for cleaning and servicing from the exterior of the enclosure. Thus, there is a need in the art for an enclosure that eliminates the need for the field splicing of drop cables, and eliminates the need for a field technician to have to open and enter the interior of the enclosure to clean, service and gain access to preterminated connectors, which may disturb and damage the contents of the enclosure.